• Restorative Dentistry and Endodontics
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• 제19권2호
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• pp.447-459
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• 1994

The purpose of this study is to evaluate of shear bond strength of light-curing composite resin to light-curing glass ionomer cement. Composite resin and glass ionomer cement have been widely used as an esthetic filling materials in dental clinics. To achieve better clinical results, sandwich technic was developed with conpensating for disadvantages of these two materials. Especially, light-curing glass ionomer cement provided greately improved bonding strength of teeth or composite resin, and then excellent clinical results can be acquired. In this study, 6 commercial light-curing glass ionomer cements(3 commercial restorative materials : Fuji II LC, Variglass VLC, Vitremer, and 3 commercial lining materials : Fuji Lining LC, Baseline VLC, Vitrebond) were devided two groups. According to manufacturer's appointment, no surface treatment was referred to N groups. Supposing. of clinical practice, surface grinding with water spray at 320 grit sand paper, 40 seconds etching with 37% phosphoric acid, 20 seconds washing, 20 seconds air drying was referred to N groups. Totally 12 experimental groups were devided, and all 120 specimens from 10 specimens of each groups were made. After light-curing composite resin was bonded to light-curing glass ionomer cement, shear bond strength was tested by Instron universal testing machine between glass ionomer cement and composit resin. The data were analyzed statistically by Student's t-test and ANOVA. The obtained results were as follows; 1. In light-curing glass ionomer cement, restorative materials showed higher shear bond strength to composite resin than lining materials(p<0.05). 2. Variglass VLC of restorative material group and Baseline VLC of lining material group have highest shear bond strength to composite resin(p<0.001). 3. In light-curing glass ionomer cement, surface grinding and acid etching reduced shear bond strength to composite resin(p<0.001)}. 4. VGN group 1s highest shear bond strength to composite resin, VBE group is lowest shear bond strength to composite resin(p<0.001).

• Restorative Dentistry and Endodontics
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• 제21권2호
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• pp.489-504
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• 1996

The purpose of this study was to compare the adaptation to the tooth structure of five light cured glass ionomer cements (Fuji II LC. VariGlass VLC, Vitremer, Dyract and Geristore). Human, non-carious fifty extracted permanent premolars stored in normal saline were used. Class V cavity preparations were created on the buccal surfaces. The occlusal margin of each cavity was placed on the enamel and the gingival margin was placed on the cementum/dentin. The teeth were then distributed at random into five groups of 10 teeth each. Group 1: Fuji II LC, Group 2 : VariGlass VLC, Group 3 : Vitremer, Group 4: Dyract, Group 5 : Geristore. The prepared cavities were restored with one of the five light cured glass ionomer cements. The manipulation of each material was handled according to the manufacturer's instructions. All samples were placed in incubator of 100% relative humidity at $37^{\circ}C$ for 24 hours. The roots of the teeth were removed with the tapered fissure bur and the remaining crowns were sectioned buccolingually through the center of restorations. The cut interfaces were gradually hand polished on sandpapers from 300 up to 1200 grit. The adaptation at the tooth/cements interface was assessed by SEM (JSM-840A, JEOL Ltd.). The results of this study were as follows : 1. Group 2 revealed the best adaptation and groups 1, 4 and 5 revealed similar adaptation pattern to the cavity walls. Group 3 revealed the worst adaptation to the cavity walls. 2. Enamel margins showed better adaptation than dentin/cementum margins with each material except group 3. 3. The hybrid layers were observed between the glass ionomer cement and dentin in groups 2, 4 and 5.

• Restorative Dentistry and Endodontics
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• 제46권4호
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• pp.57.1-57.9
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• 2021

Objectives: This study aimed to compare and evaluate the porosity and pore size distribution of high-viscosity glass ionomer cements (HVGICs) and conventional glass ionomer cements (GICs) using micro-computed tomography (micro-CT). Materials and Methods: Forty cylindrical specimens (n = 10) were produced in standardized molds using HVGICs and conventional GICs (Ketac Molar Easymix, Vitro Molar, MaxxionR, and Riva Self-Cure). The specimens were prepared according to ISO 9917-1 standards, scanned in a high-energy micro-CT device, and reconstructed using specific parameters. After reconstruction, segmentation procedures, and image analysis, total porosity and pore size distribution were obtained for specimens in each group. After checking the normality of the data distribution, the Kruskal-Wallis test followed by the Student-Newman-Keuls test was used to detect differences in porosity among the experimental groups with a 5% significance level. Results: Ketac Molar Easymix showed statistically significantly lower total porosity (0.15%) than MaxxionR (0.62%), Riva (0.42%), and Vitro Molar (0.57%). The pore size in all experimental cements was within the small-size range (< 0.01 mm³), but Vitro Molar showed statistically significantly more pores/defects with a larger size (> 0.01 mm³). Conclusions: Major differences in porosity and pore size were identified among the evaluated GICs. Among these, the Ketac Molar Easymix HVGIC showed the lowest porosity and void size.

• 대한치과보철학회지
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• 제36권1호
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• pp.26-49
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• 1998

The purpose of this study was to confirm the formation of hybrid layer and resin tags in dentin tissue and the possibility of bonding between luting cements used for the prosthesis and the resinous surface coated with resin bonding agents to prevent the dentin hypersensitivity after abutment preparation. Some resin bonding agents, which may have the possibility of bonding with polyacrylic acid as a liquid ingredient of polycarboxylate and glass ionomer cements, were selected. All-Blond desensitizer containing NTG-GMA and BPDM, Scotch-Bond Multipurpose plus containing HEMA, and XR-bond containing organophosphate were selected as a coating agent. Dental cements were zinc phosphate, polycarboxylate, and glass ionomer cement. After the exposed dentin surface of premolars was ethced with 10% phosphoric acid and coated with resin bonding agents, the morphology of treated surfaces and the resin tags and hybrid layers on sectioned surfaces were observed by SEM. Shear bond strength between the resin bonding agents and 3 kinds of cements was measured 24 hours after bonding. On the debonded surfaces of the shear bond strength tested specimens, the cement tags and the bonding sites between the resin materials and cements were examined by SEM. Following conclusions were drawn : 1. Coating of dentin with resin bonding agents had no effect on the shear bond strength of zinc phosphate cement. 2. Both of polycarboxylate and glass ionomer cements showed the increased shear bond strength by the dentinal coating with Scotch-Bond Multipurpose plus containing HEMA. However, in the case of dentinal coating with some agents containing NTG-GMA and BPDM or organophosphate, polycarboxylate cement exhibited the lowered shear bond strength, and glass ionomer cement showed the unchanged shear bond strength. 3. Complete obstructions of dentinal tubules were observed on the dentin coated with All-Bond desensitizer or XR-bond, but distinct shape of the orifices of dentinal tubules was observed consistently on the dentin coated with Scotch-Bond Multipurpose plus. 4. The hybrid layer was thickest on the dentin coated with All-Bond desensitizer, and the length of resin tags was longest on the dentin coated with Scotch-Bond Multipurpose plus. 3. On the debonded specimens which had been bonded with polycarboxylate cement or glass ionomer cement after coating with Scotch-Bond Multipurpose plus, the cement tags and the bonding sites between the resinous surface and the cements could be examined.

• The Journal of Advanced Prosthodontics
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• 제9권6호
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• pp.447-452
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• 2017

PURPOSE. To evaluate the sealing performance of Hybrid Coat and its influence on the shear bond strength of five dentin surface cements. MATERIALS AND METHODS. Six premolars were pretreated to expose the dentin surface prior to the application of Hybrid Coat. The microscopic characteristics of the dentinal surfaces were examined with scanning electron microscopy (SEM). Then, 40 premolars were sectioned longitudinally, and 80 semi-sections were divided into a control group (untreated) and a study group (treated by Hybrid Coat). Alloy restoration was bonded to the teeth specimen using five different cements. Shear bond strength was measured by the universal testing machine. The fracture patterns and the adhesive interface were observed using a stereomicroscope. RESULTS. SEM revealed that the lumens of dentinal tubules were completely occluded by Hybrid Coat. The Hybrid Coat significantly improved the shear bond strength of resin-modified glass ionomer cement (RMGIC) and resin cement (RC) but weakened the performance of zinc phosphate cement (ZPC), zinc polycarboxylate cement (ZPCC) and glass ionomer cement (GIC). CONCLUSION. Hybrid Coat is an effective dentinal tubule sealant, and therefore its combined use with resin or resin-modified glass ionomer cements can be applied for the prostheses attachment purpose.

• Restorative Dentistry and Endodontics
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• 제19권1호
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• pp.148-158
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• 1994

The purpose of this study was to compare the adaptation to tooth structure of light - cured glass ionomer cement with that of self -cured glass ionomer cement. In this study, class V cavities were prepared on the buccal surfaces of 10 extracted human premolar teeth, and teeth were randomly assigned 2 groups of 5 teeth each. The cavities of self-curing glass ionomer cement group were restored with the Fuji n. and the cavities of lightcuring glass ionomer cement group were restored with the Fuji II LC. The surfaces of glass ionomer cements were applied with All-Bond 2 adhesive, and cured with visible light. The restored teeth were stored in 100% relative humidity at $37^{\circ}C$ for 24 hours. And then. the roots of the teeth were removed with the tapered fissure bur and the remaining crowns were sectioned occlusogingivally through the center of glass ionomer restorations. Adaptation at tooth-restoration interface was assessed occlusally. axially, and gingivally by scanning electron microscope. The results were as follows : 1. On the occlusal margin, the group of self - curing glass ionomer cement showed closer adaptation to both enamel and dentin than the group of light-curing glass ionomer cement showing 5/lm gap between cement and tooth structure. 2. On the axial wall. the group of light-curing glass ionomer cement showing 5-$7{\mu}m$ gap between cement and dentin showed closer adaptation to dentin than the group of self -curing glass ionomer cement showing 10-$15{\mu}m$ gap between cement and dentin. 3. On the gingival margin, the group of light-curing glass ionomer cement showing 2-$5{\mu}m$ gap between cement and dentin(X 1200) showed closer adaptation to dentin than the group of self-curing glass ionomer cement showing 20pm gap between cement and dentin(X 600). 4. The group of self -curing glass ionomer cement showed closer adaptation on the occlusal margin than on the gingival margin, and the group of light-curing glass ionomer cement showed similar adaptation on both occlusal and gingival margins.

• Restorative Dentistry and Endodontics
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• 제20권1호
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• pp.173-182
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• 1995

The purpose of this study was to evaluate the adaptability of light-cured glass ionomer cement to cavity walls. Class V cavities were prepared on the labial surfaces of extracted bovine incisor teeth. The cavities were restored with Fuji II as self-cured glass ionomer cement and Fuji II LC, Vitremer as light-cured glass ionomer cement. Fluorescent markers (fluoreceine and rhodamin B) were incorperated into liquid and primer for a better image of microscopic observation. Restored teeth were sectioned by longitudinal and labiolingual direction. The adaptability at the tooth-restoration interface was assessed incisally, axially and cervically by confocal scanning laser microscope. Following results were obtained : 1. Chemical-cured glass iomomer cement restoration showed close adaptation on the all of the cavity walls, but, cracks formed within the cement. 2. Light-cured glass ionomer cement restoration was well adapted to the cavity walls, but showed crack in the cement adjacent to axial dentinal wall. 3. There' was no significant difference in adaptability between two light-cured glass ionomer cement restorations.

• 대한치과교정학회지
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• 제11권2호
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• pp.151-160
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• 1981

The purpose of this study was to compare the retentive values of various dental cements used for cementing the orthodontic bands on the teeth. Sound freshly extracted human premolar teeth were selected for the study. Eleven commercial dental cements (Zinc phosphate, reinforced Zinc-oxide eugenol, Carboxylate and Glass ionomer cements) were handled under standardized conditions. All cemented speciments were then kept in a thermostatic humidor cabinet regulated at $23{\pm}2^{\circ}C$ and more than $95\%$ relative humidity and tested after 24 hours and 1 week each. The force required to remove the cemented orthodontic bands from the teeth was determined on an Instron Universal Testing Machine using a modified specimen holding device with a cross-head speed of 0.20mm/min. The results obtained were as follows: 1, The retentive values of the band cemented with zinc phosphate cements and carboxylate cements were considerably higher than those of the reinforced zinc oxide-eugenol and glass ionomer cements. 2. There was no significant difference between the retentive value of carboxylate cements as compared with zinc phosphate cements. 3. The retentive value of the reinforced zinc oxide eugenol cements was lowest all of the coements. The retentive values expressed for all cements up to at least one week were highly but no significant difference was found between the 24-hour and 7 day time intervals.

• 대한소아치과학회지
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• 제32권1호
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• pp.136-143
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• 2005

이차 우식은 수복 실패의 주된 원인 중 하나로 지목되고 있으며, 이로 인해 빈번히 재수복을 하게 된다. 이차 우식은 항우식 작용이 있는 불소를 함유한 수복물을 사용하여 예방될 수 있다. 구강내에서 불소를 유리하는 것으로 알려진 글라스 아이오노머 수복재는 불소를 장기간 유리할 뿐 아니라 불소의 재충전 및 재유리 능력이 있어 불소의 저장소 역할을 할 수 있다. 따라서 본 연구는 통상의 글라스 아이오노머와 고점도 글라스 아이오노머 및 복합 레진을 대상으로 불소의 유리 양상과 불소도포를 통한 재흡수 후 유리 양상을 알아봄으로써 기존의 수복재와 새로운 수복재간의 임상적 유용성을 평가할 목적으로 시행하였다. 4종의 수복재를 대상으로 불소 유리량 및 2% NaF로 재충전 후 불소 유리량을 각각 측정하여 다음과 같은 결과를 얻었다. 1. 실험 대상의 모든 글라스 아이오노머 수복재는 초기에 다량의 불소를 유리하고 이후 점차 감소하는 경향을 보였다. 2. 2% NaF 용액을 통한 재충전 후의 유리량은 Fuji IX, Ketac Fil, Ketac Molar, Z-100의 순으로 나타났다. 3. Fuji IX을 제외한 모든 실험 대상의 수복재에서 수분의 영향으로 표면 경도는 유의하게 감소하였고 불소 재충전 후 유리량은 수분 흡수와 비례하였다(P<0.05). 4. Fuji IX이 초기 유리량에 비해 재충전 후 더 많은 불소를 유리였다(P<0.05).

• Restorative Dentistry and Endodontics
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• 제17권2호
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• pp.421-430
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• 1992

The purpose of this study was to evaluate the bond strength between the composite resin and light - cured glass ionomer cement base / liners treated by the several methods. The light - cured glass ionomer cement(Vitrebond / Cavalite) were injected into cavites prepared in acrylic plates. One hundred and twenty specimens were uniformly prepared and devided into 3 groups. For the first group, primer was not applied to glass ionomer cement. For the second group, no application of primer was undertaken and light - curing procedure to uncured glass ionomer cement surface which was covered by bonding agent was undertaken. After bonding composite resin to light - cured glass ionomer surface, the specimens, were stored in $37^{\circ}C$, 100% humidity for 1 hour. The following results were obtained : 1. The omission of application of a primer did not produce a significantly poorer bond strength. 2. Light - curing technique to uncured glass ionomer cement which was covered by bonding agent did not produce a significantly poorer bonding strength. 3. The bond strength of Cavalite to composite resin was significantly higher than that of Vitrebond. 4. There was no significant difference between two different types of composite materials(Silux-Plus / Herculite XR) when it was applied to bond to glass ionomer cement.